/*
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements. See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You under the Apache License, Version 2.0
 * (the "License"); you may not use this file except in compliance with
 * the License. You may obtain a copy of the License at
 * http://www.apache.org/licenses/LICENSE-2.0
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package org.nw.formula;

import java.util.HashMap;
import java.util.Map;

import org.apache.commons.jexl2.JexlContext;

/**
 * Wraps a map in a context.
 * <p>
 * Each entry in the map is considered a variable name, value pair.
 * </p>
 */
public class MapContext implements JexlContext{
	/**
	 * The wrapped variable map.
	 */
	protected final Map<String, Object> map;
	
	/**
	 * Creates a MapContext on an automatically allocated underlying HashMap.
	 */
	public MapContext(){
		this(null);
	}
	
	/**
	 * Creates a MapContext wrapping an existing user provided map.
	 * 
	 * @param vars the variable map
	 */
	public MapContext(Map<String, Object> vars){
		super();
		if(vars == null){
			map = new HashMap<String, Object>();
		}else{
			map = vars;
			for(String key:map.keySet()){
				Object value = map.get(key);
				if(value!=null&&value.getClass().getPackage().getName().equals("nc.vo.pub.lang")){
					map.put(key, value.toString());
				}
			}
		}
	}
	
	/** {@inheritDoc} */
	public boolean has(String name){
		return map.containsKey(name);
	}
	
	/** {@inheritDoc} */
	public Object get(String name){
		return map.get(name);
	}
	
	/** {@inheritDoc} */
	public void set(String name,Object value){
		map.put(name, value);
	}
}
